1. Field
The invention relates generally to a method for operating a network processor. In particular, the invention relates to a computer program product, method, and system for packet classification of incoming packets in multiple priority classes in a high-performance network processor, which is generally part of the final packet classification into multiple receive queues.
2. General Background
Traditionally, the classification of a packet is derived from ‘Quality-of-Service’ (QoS) parameters found in a header of the packet. This classification is typically done with a simple decoding of the QoS field found in one packet header, for example:
A Virtual Local Area Network (VLAN) bridge classifies packets according to the 3 ‘P bits’ defined as User Priority in the VLAN Header.
A Multiprotocal Label Switching (MPLS) switch classifies packets according to the 3 ‘E bits’ initially defined as Experimental bits and currently transporting the QoS value of the packet.
An IP router classifies packets according to the ‘DSCP byte’ defined as the Differentiated Services in the IPv4 or IPv6 Header.